The temporal and spatial distribution (pharmacokinetics) of potential anti-glioma agents administered into the feline brain by direct infusion are being studied. Reasons for direct infusion are avoidance of the blood brain barrier, decreased systemic exposure, and avoidance of systemic metabolic and immunologic interaction with the agent. The aim of the project is to develop the methods to administer antiglioma agents by direct infusion, and achieve an homogeneous distribution throughout the tumor volume, in a clinical setting. Agents for study will be analogous to immunotoxins, I-125 labeled iododeoxyuridine, and commercially available antineoplastic agents.